Fastening is, of course, an essential part of assembly. The placement and application of fasteners of various kinds, such as nuts, screws and bolts, is often a major time-consuming part of assembly operations. Such work is exacting and repetitive.
One aspect of a fastening operation which is often complicated to handle automatically is the seemingly simple step of taking fasteners seriatim from a collection of jumbled similar fasteners and presenting them seriatim at the point of fastener application in the proper orientation for fastening.
Because of the exacting nature of fastening operations, such as the fastener presenting and orienting step just noted, fastening operations are frequently accomplished by hand labor. Human beings can easily take a fastener from a jumbled collection of similar fasteners, move and manipulate it into the proper position and orientation for application, and then apply it in the required manner.
However, the use of human labor for such operations is sometimes considered too costly. Furthermore, the repetitive and tiring nature of the work can lead to quality control problems and/or slow-downs. Fastening often becomes the bottleneck on a production line.
The use of automatic fastening equipment, such as robot devices of various kinds, is well known in fastening operations. However, because of the exacting nature of the work and the great variety of fastening operations, such equipment is often complex and expensive.
Vibratory feeders are sometimes used in the repetitive presentation and orientation of fasteners. Such feeders dispense fasteners onto and along a track or through a tube to a driver or other fastener-applying tool. Such apparatus often includes a variety of complicated devices, such as escapements to help assure that fasteners are presented one at a time and do not spew out in uncontrolled fashion. Vibratory feeders often are complex, expensive and unreliable devices.
In any given assembly operation, a particular vibratory feeder is set up specifically to repetitively dispense a fastener of a predetermined type to a single application point. If a number of fasteners must be applied to a product under assembly, whether such fasteners are similar or dissimilar to one another, it is typically necessary to employ separate dedicated feeders for each fastener.
In summary, there is a need for inexpensive and reliable automatic apparatus for presentation of fasteners in assembly operations.